Method for the direct synthesis of ammonia



Jun so, 1925. 1,544,373

G. CLAUDE METHOD FOR THE DIRECT SYNTHESIS OF AMMONIA Filed Sept. 8, 1920500m; miziam R Ncnd H K t 7 arm D 4 mw= mfl m I UNITED STATES PAT-ENT-OFFICE;

-, oneness cannon, or new, names, ASSIGNOR, BY mun mammals, are

I nazorn, me, a conromrron or nnnawm mnon ron THE nmncr smnnsls or mom.Application filed September 6,1920. !erta1-ll'o.408,940.

. T all 101mm my c in'the reacting fgases, it would be ca able of Be itknown that I Gnonuns 01.4mm, a heating them ram 400 to- 500 abovecitizen of France, residing at Paris, France, fllBlllIlllilflltemperature of reaction, which is have invented certain new and usefulImfor example 550 C., that is to say, raising I provements in Methodsfor the Direct Synth mto 1000" to 1100 C. Obviously such a 60 thesis ofAmmonia; and I do hereby detemperature is incom atible with a yield ofclare'the following to be a full, clear, and substantially, 30% oammonia in the exact description of the invention, such as whichcorresponds to a factor of combinawill enable others skilled in the artto which tion of 50%, and the reaction, assumed to be I. it a pertainsto make and use the same. adiabatic, is ofgnecessitynotably more lim- 1sinventionrelates to improvements in ited. However, since. one of theeffects of processes involving the combination of hy'-' hyper-pressuresis to maintain at still elevat- .drogen and nitrogen under the combined.ed values the equilibriumyield for very high efl'ect of suitablecatalyzers of a suflicient temperatures, and since on the other hand,

1 6 temperature and of very gh pressures, the reaction inclines toincrease all the more ich inearller patentsI have called per- 'temrature rises through the reaction, it ressures, particularly in theUnited tatcs 'resu ts that we may nevertheless obtain ve atent No.1,332,460 of March 2 1920, for rapidly a large proportion of the 50%combiatial to or greater than 400 atmos heres, rapidly toward the;possible limit as the w 80. Process for the synthetic production ofnation almost'm an adiabatic manner, espeammonia. .cially in largeapparatus in which enormous 7 The factor of combination attains veryquantities of heatare produced in properhi h values in such a processapproaching tion to the capacity of transmission .of theBllEShllltlllll] 50%. under 800 atmospheres. wall.

Enormous quantities of heat are thus dis- There results an extremeelevation of,

enga per unit of volume of the catalyzin temperature of the reactinggases attaining cham r and the elimination 'of this heai for example 200to 250 C. inthe first efiecacross the wall of the apparatus becomes tivezones of the catalytic chamber. Then,

a more diflicult problem as the capacity of if the reacting gases travelover the catathe apparatus considered, is increased. If lyzer, followingthe usual ractice, afteni inspite of the use of exterior coils traversedhaving been raised as a who e to the initial b water, or. of a, 'jacketin which the-heat temperature of reaction by their passe e minatedproduces steam at high ressure I :through an' exchanger of temperaturein. e conforming to the above mention patent, inverse direction, and inindirect contact a the quantity of heat to be discharged per with gaseswhich have reacted, their-tem- :90

40 necessa if unit of surface of .the wall becomes greater rature willincrease rapidly from 600 (3., than the capacity of calorifictransmission 31 example, up to 800 or 850 C. n the first 'of that wall,we will be obliged toelon to effective zones of the catal zingchamber.the catalytic :Eparatus more than would be The reaction could not thencompleted as e heat could be desired unless we eliminate some of the 8.6easily. the other hand, the circulation of heat through the W811 orotherwise, during refrigeratin fluids thro bathe interior-of ,thelurther passage of the gases m; qntect the appara us is diflic t toaccomplish with the catalyze; Moreover, and It is the becauseof-thepeculiar conditions of pm essential fact on'whicli we here insist,this sure and tom rature'which should. revail. am ture of an ordernofe00. 0. would n Thisdiflicu ty of dischargin to t e out- "be t cause ofgrave danger for the resistside the heat of reaction wou d moreoveranceof the reaction-apparatus. It is pos- Y lead to another result whichwould seriously sible in fact by this excessive value to deaifect thestrength of the apparatus. To stroy the-protecting qualit of the thermicunderstand this, it is necessary to note, from and chemical insulatingbe which has been the very first, that if all of-the heat ofreaereferred to in the preceding pptents, notion cor ndlng-toa-factor'of combina-- tab] inthe United States ate'nt No. tion of suantially taken here as 1 45 594 for Protection of thewalls of anexample: and possible because of the chain rs in which reactions at veryhi he use of hyper-pressures, could be maintained temperature andpressure are eonduc the necessary of the cold gas for the gases toreact,

or the wall of the chamber of the apparatus, if this is madeof an alloyresistant only to temperatures of 600' to 700 0., or to chemical effectswhich these temperatures develop.

Under all circumstances, it is then necessary, and such is the purposeof the present invention, to find a method of limiting the temperature,other than the known means of elimination of heat across the wall of theapparatus, or by interior circulation of refri eratin fluids.

This met ed in general, involves primarily, as soon as t e reaction isstarted, to send a part regulated at will, of the gases to be treateddirectly over the catalyzer, Without heating them'previously by passagethrough an exchanger of temperature or in any other manner, and bymixing them with a part of the uses which, introduced hot, circulateover 1; e catalyzer. I utilize thus directly in the mostefiicient mannerthe Peculiar capacity of heating of these gases or limiting thetemperature 0 reaction.

This method could be a plied in various ways, of which two are ilustrated by way of example, in the accompanying drawing, in which g Fig.1 is a longitudinal sectionthrouglh an apparatus adapted to the practiceof t e invention, and

Fig. 2 is a similar view of a slightly different form of apparatus. 0

In the respective figures T or T is the catal tic chamber assumed to beof metal, avoi ing the use on its interior of an insulating lining. A orA is the inlet E 3, or I E! ,7 w exchanger of tem erature between inletsand as outlets indicated by B or B C or C is the catal zer, B or is thevalve whereby send, as soon as the reaction i started, a portion of thegas to be treated directly over the catalyzer. The other portion -isheated b its passage in the exe anger E 'or E to temperature ofreaction, and then circulates in contact with the catalyzer and ivelycombines.

F0 owing Fig. 1, an example of the operation consists in mixin with thisfraction also progressively an invcontact wi the catalyzing materialitself, the remainder which enters through a series of gases to the reof the speed ofreaction initiated, at eq temperature, by the more andmore elevated yieldof ammonia in the mixture, we understand that we havethus the possibility of the temperature so that it'does not exe gddesire,

at an& point, the value whichwe 650 for example. This value will be thegas th niplnlation of the valve o and of regulating. valves r3 Becauseof the cooling cause 1 by the introduction of cold action mass, and thecheckin preferably lower, all things bein equal, while the proportion ofgases which pass in the exchanger E. is smaller, and this proportion maybecome only one-third of the total volume of the aseous mixture, sincethe heat of reaction wiich could heat all of the gases treated b morethan 400 C. woul be. counterba anced by the heating to 600 0., thetemperature of reaction, of of the gaseous'mass not passing through theexchanger.

Fig. 2 shows another mode of operating, consisting in introducing at onetime the portion of the cold gases to the catalyzing chamber, separatedthrough a part of its length from the outer chamber "1" by a concentricshell F. This arrangement has, over the preceding, the advantagethat thecirculation of col gas in the annular ace formed between the shell andthe mber, acts as a protecting screen for the wall in the exactzonewhere the reaction f wouldbe most active, following the fact thatthe yield of ammonia here is more remote from that of equilibrium.However, the in troduction of the cold gas in the annular space oughtnot to becarried on atthe begmmng of the catalyzing chamber, for, thereactinggases there havin not yet a sufficient temperature, the a undantflow of very cold in this zone could paralyze the reaction. he poiiit ofintroduction of the cold gas ought th to be in-the zone where thereaction of thgil ilot gases has already attained a great acti 'ty,where the temperature is from 700 to 750 0., a temperature which thewall would not have to support because of the protecting effect of thecold gas previously referred to.

This cold gas penetrates progressively in the catal' zing chamberbecause of the small orifices o, pierced through the shell F,. and inorder should not tend to pass only through the u per orifices, theannular space could ed with grains of a non-catalytic material L of thesize identical with that of the catalyzer to create a pressure dropidentical throughout the device. The regulation of theragiosf lliletweenthe quzdntitbigstnlf cold gasesan o otgalel'is'm e ema- R following thein cations of a thermocou le.

In the preceding examp es the see leaving, carry with em a part of t eheat of reaction, namely, all that which is not dissipated from theexterior surface of the catalyzing apparatus. The exchanger not havingto support any difierence of pressure, the tem to does not eflectiit.The heat 0 the gas leaving could eventually be utilized externally,duction of power, before th extraction of the ammonia which the gascontains,

If, contrary to the representations 1:: the

that the greater partof the gas bell Ill

forenm lein-theprmhitting, toting protection by athermic,ai1d-chemically insulating bed, it is naturally necessary cientto permit it to act as a t It will be necessary then to maintain in thiscase a certain coollng of the exterior surface livers by t e v II Ifirst-of the patents referre w th throng sively incroa a verconsiderablerelease cooling and thereb contact of the gaseous valve D orsure-sustaining wa of the catalyzing apparatus, and to decrease co uentlthe quantity of-cold gas devalve R7? or RC. y

-In starting the ap aratu's described-hereinbefore, I may heat eectrically the interior of the a paratus by means such as have beendes'cn in other patents notably in the d to above.

followin .Figs. 1 and 2, inor a current of bylow pressure I may alsotroduce by S drogen or of nitrogen at a heated by its assage across aniron coil K or w ich is itself heated in any suitable manner.Thegas'introduced by the D and escaping by the orifice B or B gives upits heat to the catal zer and to the apparatus, and when the; wiredtemperature is attained, at the end of the catalyzing chamber, we stop,b closin the valve D or D', the cum ation o the heating gas, and sendthe total quantit of hyper-compressed reactin gases through theexchanger. The reaction lS thus initiated at activit I introduce thenthe valve or It' a progrespart of the hyper-com P (1 gas until thenormal operation is established. a f

It is evident that the present invention could be a plied to the case inwhich the synthesis 0? ammonia is carried out under pressures and inwhich by reason of the activity of the catalyzing material there isofheat per unit of vo ume of the apparatus. a

- I claim:

1. A process of producing ammonia by synthesis from a gaseous mixture ofnitroand hydrogen under high pressure in presence of a catalyst, whichcomprises maintaining the pressurefsustaining we of the reaction chamberbelow the temperature of the reaction by contact of thegaseous mixturetherewith before the gaseous mixture reaches the catalyst. 2. A processof producing amm0nia,by synthesis from a gaseous mixture of nitro andhydrogen under hi h pressure in en file presence of a catalyst, w chcomprises cooling and thereb maintaining the presof the reaction chamberbelow the temperature of the reaction b mixture therewith and directingthe gaseous mixture thus heated upon the catalyst.

3. A process of producing ammonia. by

the chamber is of metal neoessi-,

, zones thereof.

at di synthesis from a gaseous mixture of nitrogen and hydrogenundempressure inthe presence of a catalygtfihnch com rises cooling thepressure-sustil'iliing wall 0 the reaction chamber below the tem ratureof the action b contact of t e gaseous mixture therewit and directingthe gaseous mixture. thus heated upon the catalyst at successive .4. Aprocess of producing ammonia by synthesis mm a gaseousm-ixture ofnitrogen and hydrogen in the resence of a catalyst, which comprises oneing the pressure sustaining wall of the reaction chamber belowthe'temperature of the reaction by contact of a portion of the gaseousmixture therewith, heating the balance of thegaseons mixture by heatexchange with the products of the reaction and combining the twoportions in contact with the catalyst;

5. A- process of producing ammonia bysynthesis from a gaseous mixture ofnitro;- gen and hydrogen in the presence of a catalyst, which comprisescoo ing'the pressure sustaining wall of the-reaction chamber below thetemperature of the reaction b contact of a ortion of the gaseous mixturetherewith, eating the balance of. the gaseous mixture by heat exchangewith the products of the reaction and adding the first mentioned portionto the balance of the gaseous mixture at successive "zones of thecatalyst.

6. A process of producing ammonia by synthesis from a gaseous'mixture ofnitrogen and hydro "n under pressure in the presence of a catalyst,which comprises mixmg se arate portions of the gaseous mixtureerenttemperatures in contact with the catalyst and durin the reaction.7. A process 0 producing ammonia by' synthesis from agaseous mixture ofnitrogen and h drogen under ressure lll the resence o a catalyst, whiccomprises mixng separate portions of the gaseous mix- .110

'ture at different temiperatures in contact with the reaction, the

the catalyst and ed at successive rm colder portion being as stages ofthe reaction.

8. A process of producing ammonia by 116 direct thesis of its elementsunder pressure wfih comprises preheatinilonly part of the gases toreact, causing t 's part to combine in the presence of a catalyst whileadding to the part'in course of reaction 120 succemive' portions of thebalance of the gases to react.

' 9. A process of producing ammonia by direct thesis of its elementsunder pressure, w oh comprises introducing a fraction of the gases toreact after preheating to a mention chamber and send' successive notpreviously preheated portions of the balance of the gases to react'tosuccessive zones of the chamber.

10. A process of producing ammonia by direct s nthesis of its elementsunder pressure, w ich comprises introducing a. fraction of the ases toreact after preheating to a catalyst in a reaction chamber, circulatinginside the. chamber around the catalyzing material the balance of themixture and then sending it into contact with the catalyz ing material.

11..A process of producing ammonia by direct s nthesis of its elementsunder pressure, w ich comprises introducing a fraction of the gases toreact after preheating to a catalyst 1m a reaction chamber, circulatinginside the chamber around the catalyzing material the balance of themixture and then progressively distributing it to the catalyst in thechamber.

12. A process of producin ammonia by synthesis of its elements an orpressure in the presence of a catalytic body, which com prises passingincomin ases in heat-ex change contiguity to t e ot gases of thereaction, and then heating the gases to substantially the temperaturenecessary for reaction by passing the preheated gases through and inunrestricted thermal contact with the catalytic body and thence intodirect contact with the said catalytic body.

13. A process of producing ammonia by synthesis 05 its elementsunder-pressure in the presence of a catalytic body, which comprisespassing the incoming gases in heat-exchange contiguity to the hot gasesof the reaction, then passing the preheated gases through a conduitpositioned within the catalytic body and thence into contact with saidcatal tic body, and passing another portion 0 the incoming gases betweenthe interior wall of the pressure-sustainingtube and the catalytic body,and then assing said portion into thecatalytic y.

14. A proces of producin ammonia by synthesis of its elements un erpressure in t e presence ofa. catalytic body, which comlprisespreheating incoming gases by the cat evolved from the reaction andfinally heating the gases to substantiall the temperature necessary forreaction y passin them thron h and in unrestricted therma contact witthe interior of the catalytic my before actual contact with thecatalytic gases to. absorb additional a catalytic body, which comprisescooling the pressure-sustaining wall of the reaction chamber by means ofa gaseous stream contacting with the inner surface of thepressure-sustaining wall and heating the aseous mixture priorto reactionilbry passage rough the interior of the catalytic body before actualcontact therewith.

17. A process of producing ammonia by a synthesis from a gaseous mixtureof its elements under high pressure in the presence of a catalytic body,which comprisescooling below the temperature ofthe reaction thepressure-sustaining wall of the reaction chamber ad'acent the catalyticbody, by contact of t e gases therewith, and thereafter permitting thegases to absorb additional heat from the catalyst.

18. A process-of producmg-anmionia by synthesis from a a catalytic thewal of the reaction c amber that would be subject to the greatest heatof the reaction y,; which comprises cooling below the temperature of thereaction, by

contact with the incoming.- and thereafter rrnittin ture to absorb aditional lyst.

19. A processof producing ammonia by synthesis from a gaseous mixture ofits elements under high" pressure in the presence of a catalytic body,which comprises protectin'g the pressuresustaining wall of the reactionchamber from the temperature of one mixture, t e gaseous mixeat from thecata gaseous mixture of its ele 'ments imder'hl h pressure in thepresence of rtions of the hi h pressure-sustaining v the reaction at azone where the reaction is most active, by interposing the incominggases on their way to the reaction between the pressure-sustaining walland the catalytic body and; thereafter permitting the eat from thecatalyst.

20. A process of producing ammonia by synthesis from a gaseous mixtureof nitrogen and h drogen in the presence of a cata lyst, which comprisescooling the-pressuresustaining wall of the reaction chamber below thetemperature of the reaction by con- -tact of a portion of the gaseousmixture therewith and heating the balance of the gaseous mixture by heatexchange with theproducts, of the reaction.

21. A process of producin ammonia by s thesis of its elements un orpressure 111' t e presence of a catalytic body, which comprises passingthe incoming gases in heat exchange eontiguity to the t gases of thereaction, then passing the preheated gases through a conduit positionedwithin the catalytic body and'thence into contact with the catalyticbody and cooling the well of the pressure-sustaining tube y a gaseousstream contacting with the inner surface thereof.

22. A process of producing ammonia by synthesis of its elements underpressure in the presence of a catalytic body, which comprises passingthe incoming gases in heat exchange contiguity to the hot gases of thereaction, then=passing the preheated gases through a conduit positionedWithin the catalytic body and thence into contact with the catalyticbody, passing another portion of the incoming gases in contact with theinterior wall of the pressure-sustaining tube and then passing saidportion into the catalytic body.

23. A process of producing ammonia by synthesis of its elements underpressure in the presence of a catalytic body, which comprises passingthe incoming gases in heat exchange contiguity to the hot ases of thereaction, then passing the pre ieated gases through a conduit positionedwithin the catalytic body and thence into contact with said catal ticbody, and passin another portion 0 the incoming gases in contact withthe interior wall of the pressure-' sustaining tube In testimony whereofI affix my signature.

GEORGES CLAUDE.

synthesis of its elements under pressure in the presence of a catalyticbody, which comprises passing the incoming gases in heat exchangecontiguity to the hot ases of the reaction, then passing the pre ieatedgases through a conduit positioned within the catalytic body and thenceinto contact with said catalytic body, and passing another portion 0 theincoming gases in contact with the interior wall of the pressuresustaining tube.

In testimony whereof I aflix my signature.

GEORGES CLAUDE.

DISCLAIMER 1,544,373.G eorges Claude, Paris,

AMMONIA. Patent dated June France.

30, 1925. Disclaimer filed September 30, 1932,

Mn'rnon ron THE Dmacr SYNTHESIS or by the assignee, E. I. Du Pont DeNemours ct Company.

Hereby enters 12. A process of producin in the presence of a catalyticody,

exchange contiguity to the hot gases of the reaction, the temperaturenecessary contact with the catalytic direct contact with the saidcatalytic body."

"14. A process of producing ammonia in the presence of a catalytic body,wh1ch substantiall through an in unrestricted thermal the followingdisclaimer:

It disclaims claims 12 and 14, reading ammonia by synthesis of itselements under pressure which comprises passing incoming gases inheatand then heating the gases to by passin the preheated gases body andthence into for reaction by synthesis of its elements under pressurecomprises preheating incoming ases by the heat evolved from the reactionand finally heating the gases to substantla ly the temperature necessaryfor reaction contact with the interior of d .7! fiicial Gazette October25, 1.932.]

by passing them through and in the catalytic body before actual contactwith the catalytic unrestricted thermal DISCLAIMER 1,544,373.-Ge0rgesClaude, Paris, France. METHOD FOR THE DIRECT SYNTHESIS OF AMMONIA.Patent dated June 30, 1925. Disclaimer filed September 30, 1932, b theassignee, E. I. Du Pont De Nemo'urs (E Company.

Hereby enters the following disclaimer:

It disclaims claims 12 and 14, reading:

12. A process of producin ammonia by synthesis of its elements underpressure in the presence of a catalytic iody, which comprises passingincoming gases 1n heatexchange contiguity to the hot gases of thereaction, and then heating the gases to substantiall the temperaturenecessary for reaction by passin the preheated gases through an inunrestricted thermal contact with the catalytic liody and thence intodirect contact with the said catalytic body.

14. A process of producing ammonia by synthesis of its elements underpressure in the presence of a catalytic body, which comprises preheatingincoming ases by the heat evolved from the reaction and finally heatingthe gases to substantia ly the temperature necessary for reaction bypassing them through and in unrestricted thermal gOItfiGt with theinterior of the catalytic body before actual contact with the catalyticflicial Gazette October 25, 1932.]

